I want to buy Nikkor SW 90mm/f8 for 6x17 camera. I have no drakroom and mainly f or color work. I don't know how much right full off will be(1 stop or 2,3?)on 6X17 format. Anyo ne can tell me that Center filter is needed or not, and how much for that CF, if it is must? Thank you.

C. L. Yuan

Ellis Vener

23-Sep-1998, 11:55

Out of curiosity which camera will you be using this lens on? I use the Vpan 617 with a 90mm f/4.5 Grandagon and to correct for the fall off I use a Heliopan 3x neutral density center filter. The correction factor for this filter is 1.5 sto ps. For the 90mm f/8 SW-Nikkor (67mm filter size) Heliopan offers two strengths of CWF filter: the 3x (1.5 stops)(US$253); and an 8x (3 stops) (US$253). Prices are from the B&H big book. As to whether you will need a CWF for your len s you will probably have to test, but you probably will.

C. L. Yuan

24-Sep-1998, 23:07

Thank you, Ellis. I want to use SW 90mm/f8 on my home-made camera, Fuji617 alike, but with shift and multi format. I just don't like cener filter. I think since SW 90mm/f8 can be used for 5X7, may it can be used for 617 format without center filter.

Ellis Vener

25-Sep-1998, 02:06

The problem will be when you shift. The 90mm f/4.5 Grandagon has a published I.C . of 236mm and, as I wrote above, I have to use a CWF for even exposure. You wil l need to test your lens & camera using trnasparency film to see if you do or do not need a CWF. Find a dealer, (maybe Lens & Repro in NYC?) (except that you ar e in Hong Kong so maybe there is someone there?) who stocks the Heliopan filters (which are the same as the Rodenstock except for the price) and try the 0.45ND strength CWF. please let me know the result as i am thinking of switching to the smaller Nikkor lens too.

C. L. Yuan

25-Sep-1998, 04:34

If your Grandagon, I.C. of 236mm, needs CWF, I think SW 90mm needs CWF too. That is not good, but if need color slide, we have to, right? I have not see a sigle Nikon SW 90mm/f8 lens in Hong Kong till now. The center filter is even difficult to looking for. I call the Nikon delier in HK. He said I need put order first it is 8800HK$(more then 1100 US$)! I will ask my frind in Tokyo to buy one. Is that CWF also made in Japan?

Ellis Vener

25-Sep-1998, 05:39

"If your Grandagon, I.C. of 236mm, needs CWF, I think SW 90mm needs CWF too." It might or it might not; the 90mm f/8 SW has a different optical formula than all the other 90mm lenses currently made. this difference could affect eveness o f light.

"...That is not good, but if need color slide, we have to, right?" Yes if there is falloff you will need to correct, whether you are shooting trans parency or negative material.

"...I have not see a sigle Nikon SW 90mm/f8 lens in Hong Kong till now. The cen ter filter is even difficult to looking for. I call the Nikon delier in HK. He s aid I need put order first it is 8800HK$(more then 1100 US$)! I will ask my frin d in Tokyo to buy one. Is that CWF also made in Japan?"

WOW! That price is for the lens and not for the filter, right? At B&H photo in NYC (1.800.947.6650 //www.bhphotovideo.com) the price for that lens is well unde r US$900. The Heliopan CWF filter I mentioned is made in Germany. The new cost is approx. US$ 250.00. Schneider's CWF filter for their 90mm f/8 runs about US$3 70.00. As far as I have been able to tell Nikon does not make CWF filter for the ir lenses so maybe they don't need it? who knows?